Harry Ferguson obtained a patent on an agricultural tractor three-point hitch before 1930. Today, a hydraulically controlled three-point hitch with two lower draft links and an upper draft link is standard equipment on most agricultural tractors made or is available as an option. A variety of transporters have been designed and used that are attached to standard three-point linkages. These transporters include units designed for transporting articles that are or may be loaded manually, as well as units designed for excavating.
The transporters for transporting articles that may be loaded manually have a variety of different designs. The simplest transporters have a flat platform with an A-frame rigidly secured to its forward side. The three-point links attach to the A-frame and can raise the platform from the ground for movement and can lower the platform to the ground for loading and unloading. The flat platform can be loaded and unloaded from the rear edge or from either side. Side walls can be provided to keep transported articles from falling off. The sides are removable in some designs, and fixed in others. A common arrangement is a flat platform with a front wall, two side walls, and an open rear. A flat platform with sides is pivotally attached to the A-frame in an integral platform support structure in some designs. The pivotal attachment allows the platform to be tilted for unloading.
The three-point mounted hitch buckets designed for excavating also vary in design. The least complicated design includes an excavator bucket pivotally mounted on a frame and having a bottom wall, side walls and a rear wall. The bucket is filled by moving the tractor forward and lowering the bucket to the ground with the three-point linkage control system. The bucket is dumped by gravity when it is raised by the three-point hitch and a mechanical release mechanism is released. The bucket is returned to a digging position by manipulating the three-point hitch and the tractor. The more sophisticated three-point hitch mounted excavating buckets are mounted on a boom that is pivotally attached to a mounting frame supported by the three-point hitch linkage. The boom is moved relative to the mounting frame by a hydraulic cylinder and the excavating bucket is moved relative to the boom by a hydraulic cylinder. Excavating buckets are generally too small to carry bulky material. The excavating buckets that are filled by moving the tractor forward generally have bucket support frame members that partially cover the bucket, making it difficult or impossible to manually load the bucket with bulky articles.